This invention relates to a process for producing low density, low-sulfur crude oils from naturally occurring crudes.
It is known that petroleum crudes are traded on the international market by volume (e.g. U.S. barrels, 1 barrel being equal to 158,984 liters) and the lower is their density and sulfur content the more they are valuable crudes.
This because to crudes of lower density there correspond higher yields of more valuable products (gasoline, gas oil, etc., which have a lower density than the starting crude) which justifies therefore for refiners a higher cost of the crudes.
Furthermore, at a lower sulfur content a minor desulfuration requirement for refiners exists, who have to meet legal or commercial limits of sulfur content in finished products, and this will lead substantially to a lower operative cost for refiners.
Heretofore, the much diversified naturally occurring petroleum crudes have been marketed as just extracted, with only a previous decantation processing for removing any water content, and sometimes a previous stabilization processing for removing a possible excess of uncondensable gases.
Due to their enormous diversification as to chemical composition, the naturally occurring crudes are not always suitable for any potential refiner since they cannot provide the desired yields of valuable products or require for the purpose additional and expensive equipments with which only the major worldwide refineries are endowed.
This fact negatively influences the production of certain petroleum producers who have to limit the output to only reduced marketable amounts.
This is all the more so when a crude oil is of heavy type, i.e. of high density (or low API gravity); that is the crude has a high content of hydrocarbons boiling above 662.degree. F, which hydrocarbons result in a lower yield of more valuable finished products.